When on the phone, 'cookies' is a way to ask the other person if there are any listeners. This indicates that something is about to be said that should be kept under wraps. Used on land line phones to normally avoid, parents, siblings, co-workers, etc.

Person 1: Man! You should've been there last night, I was......wait, cookies?

a term used to defuse a situation otherwise thought critical.
to express the state of something as: chilling, all good, taken care of, dealt with, not a problem.
in other words: "every little thing is going to be alright"

Dog: yo dude whats good with that test? you clean?
Dude: Psh, don't even trip, its cookies. ain't no herple-burples on me dog.